Ask Your Question
0

How to use ROS Control on real robot?

asked 2018-09-21 03:51:06 -0600

pawlass gravatar image

updated 2018-09-24 02:12:55 -0600

gvdhoorn gravatar image

Hi everyone,

I would like to control the motor/servo motor using ros_control. I did courses at robotingiteacademy, but I can't understand practically what I should do now. I need information how to read and transmit data from the encoder to ROS and how to send data to the engine to be able to control it. I would be grateful for also example. I put my code.

#define ROSSERIAL_ARDUINO_TCP
#include <Timers.h>
#include <ros.h>
#include <std_msgs/String.h>
#include <std_msgs/Float64.h>

byte mac[]= {
   0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED};

IPAddress ip(10,3,2,25);
IPAddress server(10,3,2,51);
// Set the rosserial socket server port
const uint16_t serverPort = 11411;

void ros_set_current_limit( const std_msgs::Float64& cmd_msg); void ros_set_temp_limit( const std_msgs::Float64& 
cmd_msg); void ros_set_joint_min_position( const std_msgs::Float64& cmd_msg); void ros_set_joint_max_position( 
const std_msgs::Float64& cmd_msg); void ros_set_joint_position( const std_msgs::Float64& cmd_msg); float 
read_ADC(int pin, int ilosc_odczytow=1, bool odrzuc_brzegowe=0);

// CONSTANTS

const byte pin_TE   = A1; 

// VARIABLES
// ROS

ros::NodeHandle nh;
std_msgs::Float64 adc_msg;

Timer timer_adc_cs;

float odczytADC_CS  = 0.0; // aktualna wartosc czujnika pradu float odczytADC_TE  = 0.0;
temperatury float odczytADC_EN  = 0.0;

// Wartosci brzegowe
float max_current   =  10.0;

bool wystapila_komunikacja = 0;
- SECURITY

// Publishers
ros::Publisher publish_te("/sensors/temp/get",    &adc_msg); ros::Publisher publish_cs("/sensors/current/get", 
&adc_msg); ros::Publisher publish_en("/sensors/encoder/get", &adc_msg);

// Subscribers
ros::Subscriber <std_msgs::Float64>
subscriber_set_current_limit("/sensors/current/limit/set",
ros_set_current_limit);
ros::Subscriber <std_msgs::Float64>
subscriber_set_temp_limit("/sensors/temp/limit/set", ros_set_temp_limit); ros::Subscriber <std_msgs::Float64> 
subscriber_set_joint_position("/joint_position/set",
ros_set_joint_position);
ros::Subscriber <std_msgs::Float64>
subscriber_set_joint_min_position("/joint_position/min/set",
ros_set_joint_min_position);
ros::Subscriber <std_msgs::Float64>
subscriber_set_joint_max_position("/joint_position/max/set",
ros_set_joint_max_position);

// SETUP

void setup() {
   Serial.begin(115200);

   Ethernet.begin(mac, ip);

   Serial.println("aa");
   // DC Motor D9 (16bit), D4, D7
   // analogWriteResolution(12);

   pinMode(pin_PWM, OUTPUT);
   pinMode(pin_DCL, OUTPUT);
   pinMode(pin_DCR, OUTPUT);
   // // ADC A0, A1, A2
   pinMode(pin_CS, INPUT);
   pinMode(pin_TE, INPUT);
   pinMode(pin_EN, INPUT);

   nh.getHardware()->setConnection(server, serverPort);
   nh.initNode();

   delay(1000);
   nh.advertise(publish_cs);
   nh.advertise(publish_te);
   nh.advertise(publish_en);

   nh.subscribe(subscriber_set_temp_limit);
   nh.subscribe(subscriber_set_current_limit);
   nh.subscribe(subscriber_set_joint_position);
   nh.subscribe(subscriber_set_joint_min_position);
   nh.subscribe(subscriber_set_joint_max_position);

   delay(1000);

   timer_adc_cs.begin(FREQ(czestotliwosc_ADC_CS));
   timer_adc_te.begin(FREQ(czestotliwosc_ADC_TE));
   timer_adc_en.begin(FREQ(czestotliwosc_ADC_EN));

   timer_sec.begin(FREQ(czestotliwosc_SEC));
}

// LOOP
void loop() {
// ADC READ - temperature sensor

    if (timer_adc_te.available())ty
    {
      // int bledy = timer_adc_cs.errors();
      odczytADC_TE = read_ADC(pin_TE, 10, 1);
      // Wyslanie komunikatu ROS
      adc_msg.data = odczytADC_TE;
      publish_te.publish(&adc_msg);
      nh.spinOnce();

  //    timer_adc.resetErrors();
    }

  // ADC READ - current sensor
    if (timer_adc_cs.available())
    {
      // int bledy = timer_adc_cs.errors();
      odczytADC_CS = read_ADC(pin_CS, 10, 1);
      adc_msg.data = odczytADC_CS;
      // Wyslanie komunikatu ROS
      publish_cs.publish(&adc_msg);
      nh.spinOnce();

  //    timer_adc.resetErrors();
    }

    // ADC READ - motor encoder
    if (timer_adc_en.available())
    {
      // int bledy = timer_adc_cs.errors();
      odczytADC_EN = read_ADC(pin_EN, 10, 1);
      // Konwersja z ADC na wartosc odchylenia
      // adc_msg.data = 1.456;
      adc_msg.data = (odczytADC_EN / 1024) * 100;
      // Wyslanie komunikatu ROS
      publish_en.publish(&adc_msg);
      nh.spinOnce();
  //    timer_adc.resetErrors();
    }

   // SECURITY
   if (timer_sec.available()) // Gdy przekroczono time odczytu ADC, uruchom odczyty
   {
   }
}

// FUNKCJE
void helper_sortowanie(int a[], int size) {
   for ( int i = 0 ; i < ( size - 1 ) ; i++)
   {
     for ( int o = ( i + 1 ) ; o < size ; o++ )
     {
       if(a[o] > a ...
(more)
edit retag flag offensive close merge delete

Comments

hw_interface

dinesh gravatar imagedinesh ( 2018-09-21 03:53:29 -0600 )edit
3

@dinesh, I've turned your answer into a comment. It was too short and as-is, not of much help to the OP.

ros_control cannot be used directly on Arduinos, so if you can provide a little more detail on the setup that you have in mind, that would be good.

gvdhoorn gravatar imagegvdhoorn ( 2018-09-21 05:43:22 -0600 )edit

1 Answer

Sort by ยป oldest newest most voted
1

answered 2018-09-23 00:56:00 -0600

dinesh gravatar image

updated 2018-09-23 00:57:56 -0600

You can write your own hw_interface program in either c++ or python where u can add the libraries to read the hardware information or send the motor commands, for eg. u can pigpio or wiring pi library to interface your hardware to your ros controller. Than u can easily use ros control to control any robot you want. Only part which should be modified is the hardware interface where you add the external libraries generally to communicate the hardware(actuator, encoder) .

edit flag offensive delete link more

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

Question Tools

2 followers

Stats

Asked: 2018-09-21 03:51:06 -0600

Seen: 434 times

Last updated: Sep 24 '18